Hydraulic valve lifters use the engines oil pressure to expand the lifter which provides a zero valve lash clearance. This prevents the valves from tapping. When the engine is shut off, a valve and spring in the lifter keep it expanded and retain the oil within the lifter.
1. Pain that injects from your back or neck to your hand or foot. Shooting or cutting pain is what pain from a herniation feels like. If this pain goes all the way to your hand or foot then this possibly a disc herniation. Pain that ends before crossing your knee or elbow is most likely to be referred pain.
What are the symptoms? When a herniated disc presses on nerve roots , it can cause pain, numbness, and weakness in the area of the body where the nerve travels. A herniated disc in the lower back can cause pain and numbness in the buttock and down the leg. This is called sciatica (say sy-AT-ih-kuh).